The invention resides in a motion transmission mechanism for the control of an internal combustion engine which is arranged between a control member and an engine power output control element, especially a butterfly valve of the internal combustion engine and which includes at least one return spring and an input lever connected to a control input member end and an output lever connected to the engine output control element, one of the levers having a guide slot and the other having a projection received in the guide slot for the transmission of motion from one to the other of the levers and to the engine output control element for the control of the engine.
DE 40 36 956 C1 discloses a motion transmission mechanism which comprises a double-arm input lever with a projection and, cooperating therewith in the same rotational sense, an output lever adapted to operate a controller and having a guide slot receiving the projection of the input lever. The guide slot has first and second sections arranged at an angle with respect to one another which, in cooperation with the projection, provide for a reduction of the motion transmission in the partial load range of the engine and for increased motion transmission in the upper load range of the engine.
Arranged between the input lever and the output lever is a tension spring which, upon actuation of the motion transmission mechanism, is first tensioned in the partial load range represented by the first connecting link slot section but, upon load increase, is detensioned in the upper load range as represented by the second guide slot section as the distance between the mounting points of the spring is then reduced. For a reliable closing of the throttle valve return springs are utilized.
It is the object of the present invention to provide a motion transmission mechanism which is simple and more reliable and with which the mechanism can be safely returned to idle position from any lever position.